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Results for “SPECIFIC GRAVITY”

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At least 19 recordsLinked to original sources
PubMed1998

Determining specific gravity, specific heat, and surface area of rabbits for a possible thermodynamic approach to body temperature change.

In order to investigate the mechanisms of body temperature change from a thermodynamic aspect, we investigated the specific gravity, specific heat and surface area of rabbit in situ. We obtained the following results. 1. The specific gravity of normal, shorn and ecdysed rabbits is 0.94, 0.95 and 0.97, respectively. 2. The specific heat of normal, shorn and ecdysed rabbits is 0.95, 0.89 and 0.69 cal/g.K, [corrected] respectively. 3. The surface area of the rabbit was also measured by using the weight of aluminum foil which covered the surface.

Animals↗
PubMed1983

Evaluation of ames Multistix-SG for urine specific gravity versus refractometer specific gravity.

A comparison of urine specific gravity by a commercially available multiple reagent strip (Multistix-SG; Ames Division, Miles Laboratory) versus refractometer specific gravity (TS Meter; American Optical Corporation) was performed on 214 routine urine specimens. Agreement to +/- 0.005 was found in 72% of the specimens (r = 0.80). Urine specific gravity by the Multistix-SG showed a significant positive bias at urine pHs less than or equal to 6.0 and a negative bias at urine pHs greater than 7.0 in comparison to refractometer specific gravity. At concentrated (specific gravity greater than or equal to 1.020) specific gravities, up to 25% of urine specimens were misclassified as not concentrated by Multistix-SG specific gravity in comparison to refractometer specific gravity. The additional cost of the specific gravity reagent to a multiple reagent test strip in addition to the poor performance relative to refractometer specific gravity leads to the conclusion that including this specific gravity methodology on a multiple reagent strip is neither cost effective nor clinically useful.

Humans↗
PubMed1979

The effect of seasonal changes and socio-economic status on urinary pH and specific gravity.

Specific gravity and pH of urine in the dry and the wet season in three socio-economic Nigerian groups have been studied. Samples were collected at 7 a.m., 11 a.m. and 3 p.m. High-income subjects had a significantly lower urinary pH than low-income. During the wet season pH values were lower than in the dry, but not significantly so. During the day S.G. values did not differ, neither did they in different seasons. But there were significant differences between high and low income groups. S.G. and pH samples of high and low income groups were similar in children and in their parents. In medical students S.G. and pH in 24-hour urines were similar to the morning value of high and middle income groups and were not affected by season, but the volume was. The relevance of these findings is discussed relative to the rarity of urinary calculi in Nigerians.

Adult↗
PubMed1978

Analysis of cerebrospinal fluid specific gravity.

The specific gravity of 71 CSF samples from clinically normal dogs ranged from 1.004 to 1.006, with a mean of 1.005. A 3-year retrospective study of CSF samples obtained from 124 animals suspected of having neurologic disease revealed only 30 samples (24.2%) having a specific gravity greater than 1.006. Diagnostic or prognostic value from CSF specific gravity determination was not recognized.

Animals↗
PubMed2006

The value of urine specific gravity in detecting diabetes insipidus in a patient with uncontrolled diabetes mellitus: urine specific gravity in differential diagnosis.

When a patient with diabetes mellitus presents with worsening polyuria and polydipsia, what is a sensible, cost-effective approach? We report the unique coincidence of type 2 diabetes mellitus and diabetes insipidus. A 46-year-old woman with poorly controlled type 2 diabetes complained of polyuria with a daily output of 5 L. Although urinalysis demonstrated significant glucosuria, diabetes insipidus was suspected owing to a low urine specific gravity (1.008). The low specific gravity persisted during a water deprivation test. Ultimately, diabetes insipidus was confirmed when urine specific gravity and urine osmolality normalized following desmopressin administration. This case emphasizes the importance of accurately interpreting the urine specific gravity in patients with polyuria and diabetes mellitus to detect diabetes insipidus.

Diabetes Insipidus↗
PubMedDate not supplied

Determination of the specific gravity of human pineal.

Specific gravity values for the pineal gland in any species are lacking. These data are necessary for calculating and interrelating pineal weight and volume. This report deals with the specific gravity of human pineal gland. The specific gravity of fresh, unfixed human pineal has been determined to be 1.197 +/- 0.036 SEM at 20 degrees C (N = 11) using water as the measuring medium. By contrast, human brain has been reported in the literature to have a specific gravity of 1.036. Specific gravities of human pineals fixed in Bouin's fluid, Bouin's fluid followed by 80% ethanol, 80% ethanol, and embalming fluid were found to be 1.113 +/- 0.025 (N = 5), 0.941 +/- 0.009 (N = 5), 0.990 +/- 0.022 (N = 3), and 1.149 +/- 0.021 (N = 7), respectively. These are corrected values accounting for the specific gravities of the respective measuring fluids. It is shown that the specific gravity of human pineal as derived in this study is directly applicable to calculations of pineal volumes and weights not only in humans, but in other species as well.

Aged↗
PubMed1988

Indomethacin and dexamethasone treatment in experimental neoplastic spinal cord compression: Part 1. Effect on water content and specific gravity.

Water content and specific gravity were measured in the cervical, high thoracic, thoracic, and lumbar segments in an experimental model of neoplastic epidural spinal cord compression in rats harboring a thoracolumbar tumor. Increased content of water was observed only in the compressed lumbar cord segments of paralyzed rats (P less than 0.04). A progressive increase in specific gravity values of the compressed segments accompanied the increasing severity of neurological dysfunction (P less than 0.003 in paraplegic rats). Electron microscopy of the compressed cord revealed enlarged interstitial spaces, myelin breakdown, and extravasated blood cellular elements. Treatment with dexamethasone (10 mg/kg q 12 hr x 3) failed to reduce the increased content of water, but corrected specific gravity changes. Treatment with indomethacin (10 mg/kg q 12 hr x 3) reduced both elevated water content and specific gravity values back to normal levels. In untreated animals, the interval between the first neurological sign (limp tail) and paraplegia was 2.8 +/- 0.34 days (mean +/- SE). Treatment with dexamethasone lengthened this period by 28.6% (P less than 0.05); treatment with indomethacin lengthened it by 66.4% (P less than 0.005). We conclude that, because the specific gravity measurements in this model reflect complex pathophysiological processes, their translation into water content values is not advisable. Pharmacological intervention with indomethacin compares favorably with dexamethasone in reduction of spinal cord edema and in delaying the onset of paraplegia.

Animals↗
PubMed1993

The effects of diaper brands, urine volume, and time on specific gravity measurement.

Nurses use urine specific gravity to assess fluid volume status in pediatric patients. Specific gravity of five leading brands of disposable diapers was measured to determine the effects of diaper brand, urine volume, time elapsed, and method of specific gravity measurement comparing the two methods of refractometry and N-Multistix SG (Ames Division, Miles Inc., Elkhart, IN). Immediately after a baby voided 20 mL of urine into any disposable diaper, the specific gravity by refractometer accurately compared with the control standard. Measurement accuracy by N-Multistix SG was only assured if Pampers (Procter & Gamble, Cincinnati, OH) were used. However, both methods were inaccurate at 4 hours with 20 mL of urine. Immediately after a baby voided 40 mL of urine into any disposable diaper, both methods were accurate when compared with the control. At 4 hours, only Pampers and Chux (Procter & Gamble, Cincinnati, OH) were accurate by refractometry, and Pampers alone was accurate by N-Multistix SG.

Humans↗
PubMed1995

[Evaluation of a test strip for the determination of urine specific gravity in the dog].

The specific gravity of 80 randomly chosen urine samples from healthy dogs without polyuria/polydipsia and from a few dogs with polyuria/polydipsia was measured by refractometry and by test strip method (sg test strip). Urine osmolality and pH were also measured and the urine samples were examined for the presence of glucose. In accordance with earlier observations, there was an excellent correlation between the specific gravity determined by refractory and the osmolality (r = 0.98). The results obtained with the sg test strip correlated poorly with those obtained by refractometry (r = 0.39) and poorly with the osmolality (r = 0.36). In 77.5% of the samples the specific gravity determined with the sg test strip differed by more than 0.005 from that determined by refractometry. After correction of the sg test strip results by +0.005 for urine pH > or = 6.5, this percentage decreased to 60%. The results for the refractometer and sg test strip were significantly different (P < 0.001). These results indicate that the sg test strip investigated is unsuitable for use to determination of the specific gravity of canine urine.

Animals↗
PubMedDate not supplied

Influence of the load of nylon capsules on their passage through the digestive tract and specific gravity.

The passage and specific gravity of nylon capsules were evaluated in five trials. In individual trials, different lactating cows were fed the same diet consisting of maize silage, alfalfa hay and concentrate. In each trial the different feeds (or no feed) were used to fill the capsules. The capsules were made of nylon cloth (42 microm pore size, 10 mm external diameter). The different weights of the load (L1-L5) were obtained using a combination of 2 and 3 mm stainless steel balls. The highest recovery of the capsules was obtained with the L3 and L4 loads (91.4 and 92.3%, resp.). After 14 hours of incubation in the rumen, the calculated values of functional specific gravity of the capsules ranged from 0.92 to 2.05 g x cm(-3). It was concluded that L3 (one 2 mm and one 3 mm ball) was the suitable weight of the load.

Animal Feed↗
PubMed1991

Differentiation of naphthalene and paradichlorobenzene mothballs based on their difference in specific gravity.

The present study was conducted to measure the specific gravities of paradichlorobenzene and naphthalene mothballs and compare them with the specific gravity of a saturated aqueous solution of sodium chloride (1.197). The specific gravities of 450 paradichlorobenzene mothballs from 5 manufactures and 150 naphthalene mothballs from 2 manufactures were measured with a specific gravity meter. The mean specific gravities of paradichlorobenzene mothballs were between 1.429 and 1.437 (p = 0.99). On the other hand, the mean specific gravities of naphthalene mothballs were between 1.094 and 1.100 (p = 0.99). Based on the fact that paradichlorobenzene mothballs sink in a saturated solution of salt whereas naphthalene mothballs float on it, these 2 kinds of mothballs ought to be rapidly and accurately distinguished in clinical settings.

Chlorobenzenes↗
PubMed1980

Effects of radiographic contrast media on results of urinalysis, with emphasis on alteration in specific gravity.

The effect of radiographic contrast medium on the urine specific gravity of ten clinically normal dogs was evaluated. Urinary excretion of different dosages of intravenously administered triiodinated contrast medium caused significant alterations of urine specific gravity. The magnitude of change was related primarily to preinjection urine specific gravity values rather than dosage of contrast medium. In general, preinjection urine specific gravities < 1.040 were increased 15 minutes after injection of contrast material, whereas preinjection urine specific gravities > 1.040 were decreased 15 minutes after injection of contrast medium. A linear relationship was identified between the concentration of radiographic contrast medium in either distilled water or urine and the specific gravity of these mixtures. This simulated the effects of radiologic contrast medium on urine specific gravity when used for retrograde urethrocystography. Results of the investigation indicated that urinary excretion of radiographic contrast media significantly alters urine specific gravity values in normal dogs and renders postinjection urine samples unsuitable for diagnostic evaluation of renal tubular concentrating capacity. In addition, previously reported errors in urine protein, glucose, and sediment evaluations attributed to radiographic contrast media were reviewed.

Animals↗